What is Psoriasis?
A condition which usually results in the skin becoming red, flaky, crusty and itchy. The affected skin usually looks like it is covered in silver scales.
In most cases the patches will appear on the elbows, the scalp, lower back and the knees, however psoriasis can appear anywhere on the body. Most patients will have a few small patches but, in some cases, they can be large, widespread, itchy and painful.
Psoriasis affects approximately 2% of the UK population. In most cases it develops in children and adults under the age of 35, however it can start at any age. Psoriasis affects both men and women equally. The severity of the condition varies from patient to patient. Someone may just experience a minor irritation from the condition whereas in others it can have a major impact on their day to day lives.
Psoriasis is classed as chronic (long-lasting) condition that usually involves periods of time when the patient will have zero or very mild symptoms, followed by periods of time when the symptoms flare up and become more severe.
What causes psoriasis
Psoriasis is the result of your body over producing skin cells. Where skin cells would normally take 3-4 weeks to be replaced, in psoriasis this process is occurring every 3-7 days instead. The resulting build-up of skin cells gives way to the distinctive patches which are usually associated with psoriasis.
Although the cause of psoriasis is not fully understood, it is thought to be related to a problem with the patient’s immune system. Your own body’s defence mechanism against disease and infection begins to attack the patient’s healthy skin cells by mistake. Although it is still unclear, it is believed psoriasis may have a genetic factor to it as we often see the condition running in families.
Triggers can cause someone’s symptoms to become worse. These can vary for each individual and can include stress, injury, infections or certain events. Psoriasis is not contagious and cannot be passed from person to person.
A more complete list of triggers can be accessed by clicking here for the NHS reference source.
In most cases, your GP will be able to diagnose psoriasis by looking at the rash. In rare cases a small sample (biopsy) may need to be examined under a microscope to make a diagnosis. This would be the case when it is necessary to rule out other skin conditions such as lichen planus, dermatitis, etc.
Some patients will also require a referral to a dermatologist for diagnosis and treatment. This happens when the GP is uncertain of the condition or if tried treatment options have failed and specialist treatment is required. Referral to a rheumatologist may also be needed if your GP suspects you have developed psoriatic arthritis (blood tests and x-rays may be required to rule out other conditions such as rheumatoid arthritis).
There is no cure but there is a wide array of treatment options now available for psoriasis. The aim of treatment is to keep the symptoms and condition under control. In most cases this can be achieved by treatment obtained from your GP. In a small minority this will need to be referred to specialist care in a secondary setting which is initiated by a dermatologist.
Identifying the correct treatment for patients remains the biggest challenge for clinicians. Usually a trial and error approach is undertaken and patients are encouraged to report treatment failure to their prescriber as soon as possible so an alternative therapy can be tried.
Treatment usually falls into one of three categories –
• Topical – emollients, creams, etc.
• Phototherapy – ultraviolet (UV) light therapy
• Systemic – oral and injectable medication which works throughout the body, e.g. immunosuppressants.
Initial treatment involves the use of emollients. These work by protecting the skin and by reducing water loss. This works well for mild psoriasis and aims to reduce itching and scaling. If you are using other topical treatments, these should be applied 30 minutes after the emollient.
If moisturising preparations do not have the desired effect on their own, steroid creams and ointments (topical corticosteroids) can be added in. The treatment aim is to reduce inflammation of the skin, which in turns slows down skin cell production and reduces itching. Topical corticosteroid creams can be mild, strong, potent or very potent in strength. The stronger preparations will be prescribed if the weaker ones have not worked. They should only be used on the affected skin sparingly. Overuse can lead to the skin becoming thin.
Other treatments can include –
• Vitamin D analogues
• Calcineurin inhibitors
• Coal tar
• Phototherapy (UVB, PUVA or combined)
• Tablets, capsules or injections (methotrexate, Ciclosporin, Acitretin, Etanercept, Adalimumab, Infliximab, Ustekinumab and some newer drugs)
A full explanation of these treatments can be found by clicking here to access the NHS reference website.